Rarest and Most Expensive Opals: Treasures Born from Fire and Light The Rarest and Most Expensive Opals inspire fascination because they combine geological magic with vibrant color displays. These extraordinary stones form through natural processes that take millions of years, which increases their value and desirability. Collectors admire the electric flashes of red, green, and blue that dance across each surface. Read More@ https://www.gemstonesforsale.com/blogs/gemstone-buying-guide/most-rarest-expensive-opals-in-the-world